Air-feed-controlling device



Jan. 14, 1930. L. c. BAYLES 1,743,090

AIR FEED CONTROLLING DEVICE Filed Sept. 30, 1927 JNVEN TOR.

HASAT ORNEY.

1 element.

Patented Jan. 14, 1930 UNITED STATES LEWIS C. BAYLES, OF EASTON, PENNSYLVANIA, ASSIGNOR T INGEBSOLL-RAND COM- M PANY, OF JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY .AIR-FEED-CONTROLLING DEVICE Application filed. September 30, 1927. Serial No. 223,039.

This invention relates to fluid actuated rock drills, but more particularly to an air feed controlling device for rock drills of the stoper type.

The objects of the invention are to regulate the pressure in the air feeding element of the drill in an improved and simplified manner and to economize in the pressure fluid consumption of the feeding element.

The foregoing objects are attained in the present instance by means of a fluid actuated valve which, in one of its position, may form a part of the exhaust passage through which pressure fluid is exhausted from the feeding "When in that position the valve may also serve to prevent the admission of pressure fluid into the feeding element until the pressure therein has dropped to a value sufliciently low to prevent an unduly rapid advance of the drill towards the work whenever conditions in the drill hole are such that the best drilling results may be obtained by applying only a light pressure to the working implement.

Other objects will be in part obvious and in part pointed out hereinafter.

The invention'consists of the combination of elements and arrangement of parts having the general mode of operation substantially as hereinafter described and claimed and illustrated in the accompanying drawing, in which the figure illustrates a portion of a stoper type rock drill in vertical section having the invention applied thereto.

Referring more particularly to the drawing, A designates a percussive cylinder in which disposed a reciprocatory hammer piston B for delivering blows of impact to a working implement such as a drill steel (not shown). A closure is provided for the rearward end of the cylinder A in the form of a back cylinder washer C which has a flat surface D at its rearward end to form a seat for an oscillatory plate valve E. The plate valve E may be of a well known type and in this instance is disposed about a rifle bar F which interlocks slidably with the piston B in the usual manner for imparting r0- tary movement to the working implement.

Seated on the flat surface D of the'backcylinder washer C is a back head G which encircles the rifle bar F- and is recessed to form a valve chamber H for the reception of the valve E. In addition to the functions described the back head G also acts as a seat for one end of a rifle bar head J wherein are disposed the usual pawl devices K adapted to cooperate with a toothed rotation ratchet L seated on the back head Gr.

The rifle bar F in this instance is held against movement in a rearward'direction by a head block O which is seated on the rearward end of the rotation ratchet L and has a reduced flanged portion P which extends into the rotation ratchet L, both for centralizing the head block with respect to the rotation ratchet and also to act as an abutment for the head J of the rifle bar F.

A throttle valve Q, preferably of the rotatable type is disposed in the head block 0 and has a lever B.- whereby said throttle valve may be manipulated. A bore S in the throttle valve Q may be in constant communication with a source of pressure fluid supply as is customary in devices of this type, and such pressure fluid may be conveyed to the valve chamber H through a port T in the throttle valve and pasage U wherewith the port registers, said passage U being formed in the head block 0, the rotation ratchet Land in the back head G. a

The pressure fluid admitted into the valve chamber H is distributed by the valve E and flows to the rearward and front ends of the cylinder through inlet passages V and \V respectively. p The feeding element for advancing the rock drill towards the work-in this instance comprises a feeding cylinder X and a feed piston Y disposed in the cylinder X.- .The

screwed on the end of the rod 6 for holding the head Z thereon.

In accordance, with the present invention,

the throttle valve Q is provided'with a port f 'which, in the open position of the throttle valve, registers with an inlet passage 9 in the head block 0 forconveying pressure fluid to the feeding cylinder X. In the present instance. theinlet passage 9 terminates. in a valve chamber it formed in" the head block 0, and a. passage affords communication between the. valve. chamber h and the feeding cylinder Preferably a second 1 passage k is :formed in the head block 0 for exhausting pressure fluid; fromthe. feedingcylinder X into the valve chamber it, said passage is opening in this instance into the valve chamber h at the lowermost endof the said valve chamber.

At the opposite end ofthevalve chamber h is .an exhaust passage 0 which leads through the rotation ratchet L', the back head G and .the back cylinder washer C and preferably terminates at point in the cylinder A where it registerswith a passage p in-a rotation han- .dle q. Therotation handle 9 in this instance projectsithrough an aperture 1 in the cylinder Ai andris. clamped in. position by a nut s screwedonthe endofsaid rotation handle.

Suitable means are provided for controllingthewexhaust.ofpressure fluid from the feeding cylinder. Themeans in thepresent instance consist of a relief valve t preferably seated .in abushing u disposed in theoutermost. or freehend of the. rotation'handle q. The, relief valve: t is preferably normally held closed by a spring '0 which is seated with one end against the relief valve band with its other end against a spring seat w disposed at't-h'e. innermost end of the bushing u. A stemw carried by the relief valve t extends sliidably into a bore y in the bushing 20 and has a reduced neckw portion 2 to permit the passage of pressure fluid around the stemw to ports 2 in thevbushing u opening into an 7 external-groove 3 in the bushing up The groove3 may be of a suitablelength to register with a passage 4 in a grip portion 5 of the rotation handle 9.

The relief valve 15, aswill be observed, is of the reciprocable type and the means whereby said relief valve maybe-unseated consist :in this instance of a push rod .6 having an in- The push rod 6 may be of a length to ex- I tend beyond the end of the rotation handle 9, the outer end 10 of said push rod being of somewhat smaller diameter than the head 7 and carrying a button 11 conveniently situ- I ated to enable the operator to manipulate the button 11 with the same hand wherewith he grasps the grip portion 5 of the rotation handle 9. The bushing u; and the pushrod 6 are held in operativepositionby a hollow threaded plug 12screwed inthe outer end of the rotation handle 9.

Disposed in the valve chamber it is a feed valve-13 whichhasarecess 14 for the remapl; tion of a spring 15 whereby the valve 13 is normallyheld in the lowermostend of the valve chesth. In thelowermost end ofthe valve 13 isformed a port 16-.and thiszport 16 forms the restricted portion of the path provided for the escape of pressure fluid from the feeding cylinderX to control the volume of pressure, fluid which may be exhausted from said feeding cylinder.

' In the peripheryof the valve 13 is. formed an annular groove 17"which normally affords communication between the passages g and j for admittingpressure fluid into the feeding cylinder X. 7 In-thedrawing, the; air feeding controlling means .are shown in the-positionswhich' they will assume when the air feedin cylinder X is exposed to line pressure. finder these conditions, the throttle valve twillremain closed and the, valve '13 will occupy its lowermost'position inthe valvechest h to admit pressure fluid through the passages .g and-j and the-annular groove 17 ,into the feeding cylinder foradvancing the drill :towardsthe work. 7

During'normal drilling thespring15 will hold the valve 13 in the position described. If, however, asoccasionally happens in drilling operations, theworki'ng implement encountersreither airsoft or an, unusually hard stratain the material being drilled, in either case'ofwhich it is desirable to reduce the pressure against the working implement and andthe. relief-valve t may bereleased so that momentarilythere. will be no pressure acting on the uppermost end of the valve 13 other than that of the spring 15. Owing to the fact that the passage kopens directly againstthe lowermost. end of the valve 13 pressure fluid from the feeding. cylinder X will act against the said :valVe and .1 move it to its uppermost position in the valve chest 70. In this position of the valve 13 the annular groove 17 will be moved out of re istry with the passage y', thus cutting off the supply of pressure fluid into the feeding cylinder X and with the relief valve 2? in its open position pressure fluid may escape through the passage is, the restricted port 16, thence through the recess 14 and the exhaust passages leading therefrom through the rotation handle to the atmosphere.

When conditions in the drill hole again permit the application of a greater pressure to the working implement the button 11 may be released and the throttle valve 2? will then be closed by the spring a. Immediately upon the closing of the throttle valve t pressure fluid will flow from the feeding cylinder through the port 16 into the upper end of the valve chest h. Both ends of the valve 13 will then be constantly exposed to pressure fluid of the same pressure and the spring 15 will then move the valve 13 to its initial position, thus again opening communication between the passages g and j for the admission of pressure fluid into the feeding cylinder X.

The present invention has been found to effect a considerable economy in the matter of pressure fluid required for actuating the feeding element, since, whenever it is desired to reduce the pressure in the feeding element the supply thereto is also simultaneously cut off, thus eliminating the necessity of constantly exhausting a greater amount of pressure fluid from the feeding cylinder than is being admitted thereto.

I claim:

1. In an air feed controlling device for rock drills, the combination of a percussive cylinder and an air feeding cylinder, a head block between the cylinders having an inlet passage for conveying pressure fluid to the air feeding cylinder, an exhaust passage leading from the air feeding cylinder to the atmosphere, and a valve controlling the passages normally exposed at both ends to the pressure fluid of the same pressure, said valve being normally open to admit pressure fluid from a source of supply through the inlet passage into the feeding cylinder and adapted to normally remain open.

2. In an air feed controlling device for rock drills, the combination of a percussive cylinder and an air feeding cylinder, a head block between the cylinders having an inlet passage for conveying pressure fluid to the air feeding cylinder, an exhaust passage leading from the air feeding cylinder to the atmosphere, a valve controlling the passages exposed at both ends to pressure fluid whereby said valve is actuated to close the inlet passage and open the exhaust passage upon a reduction of pressure on one end of the valve, and a spring acting on the valve to 'sagesexposed at both ends to pressure fluid hold said valve normally in a position wherein pressure fluid may constantly flow from the inlet passage into the air feeding cylinder.

3. In an air feed controlling device for rock drills, the combination of a percussive 1 cylinder and an air feeding cylinder, a head block between the cylinders having an inlet passage for conveying pressure fluidto the air feeding cylinder, an exhaust passage leading from the air feeding cylinder to the atmosphere, a valve controlling the passages and constantly exposed at both ends to pressure fluid from the feeding cylinder, a spring acting against one end of the valve augmenting the pressure fluid acting there on to overcome the pressure against the opposite end of the valve, and means controlling the outlet opening of the exhaust passage for exhausting pressure fluid from one 35 end of the valve, thus enabling the pressure fluid at the other end of the valve to actuate the valve into a position for cutting off communication between the inlet passage and the feeding cylinder and for permitting the. exhaust of pressure fluid from the feeding cylinder through the exhaust passage to the atmosphere.

4. In an air feed controlling device for rock drills, the combination of a percussivej cylinder and an air feeding cylinder, a head block between the cylinders having an inlet passage-for conveying pressure fluid to the air feeding cylinder, an exhaust passage leading from the air feeding cylinder to the ittlllOS-Ld-W phere, a valve controlling the passages exposed at both ends to pressure fluid from the air feeding cylinder, a spring'acting against one end of the valve augmenting the pressure fluid acting thereon to overcome the presit! sure acting against the opposite end of the valve, and manually operable means controlling the outlet opening of the exhaust passage for exhausting pressure fluid from one end of the valve, thus enabling the pressure 15. fluid at the other end of the valve 'to'actuate the valve into a position for cutting off communication between the inlet passage and the feeding cylinder and for permittingthe exhaust of pressure fluid from the feeding cylinder through the exhaust passage to the atmosphere. y

5. In an air feed controlling device for rock drills, the combination of a percussive cylinder and an air feeding cylinder, a head block 511120 between the cylinders having an inlet passage for conveying pressure fluid to the air feeding cylinder, an exhaust passage for the feeding cylinder, a valve controlling the pasfrom the air feeding cylinder, said valve having a port to control the volume of pressure fluid exhausting from the air feeding cylinder into the exhaust passage, a spring acting against one end of the valve augmenting the pressure fluid actingthereon to overcome the pressure actingsagainst the opposite end of the valve,-and;manually= operable means controlling the outlet opening of the exhaust passage fon'exhaus tingzthe pressure fluid acting against; one endof. the cvalve thus enabling the pressure fluid acting against the other end ofithe valve to actuate the valve into a posit'ion for cutting: off communication between the inletipassage and thefeeding cylinder and fon permitting the exhaust of pressure fluid frornthefeeding cylinder through the port and the exhaust-passage to'the atmosphere.

GeIn' an air; feed controlling device for rock drills, the: combination of" a percussive cylinder and an air feeding cylinder, a head block between the cylinders-having an inlet passage for conveying pressure fluid to the air; feeding cylinder, anexhaust passage for the feeding: cylinder, afeed' valve controlgyto-the'drill having a-passage registering with the'exhaust passage, a relief valve in the retationhandle controlling the exhaust passage, and'a manually.- operable push rod for opening the'relief valve to-exhaustpressure fluid acting against one end of the feed-valve, thus enablingathe pressure fluid acting against the other end" of'the valve to actuate the feed valve into-a; position for cutting off coinmunication between the inletpassage and the mitting the escape ofpressure fluid from the feeding cylinder through the port and the exhaust passage to the atmosphere.

thus enabling the pressure 'fiuidactingzagainst the other end of the feed-valve to actuate the feedvalve into a position for cuttingofl comlnunicationbetween the inlet passage :and the feedingzcylinderand for simultaneouslypermittin'gthe escape of pressure fiuidfrom the feeding cylinder through the port and: the exhaust passage to-the atmosphere; In testimony whereof I: have signedithis specification.

LEWIS GI BAYLES;

feeding cylinder and for simultaneously per- 7. In an'vair feed controlling device for c rock drills, the combination of a percussive cylinder and anair feeding cylinder, a head block'between the cylinders having an inlet passage-for conveying pressure fluid to the air feeding cylinder, an exhaust passage for.

fluid from the; air feeding cylinder, said valve having aport to control the volume of pressure fluid exhausting. from the air feeding cylinder into theexhaust passage, a spring acting against one end of the valve augimenting-the pressurervfluidacting-thereon to overcome the" pressure acting against the opposite end of the valve, a rotation handle se-V cured to the drill havinga passage, a spring pressedzreliefvalve in the free end of the rotation handle controlling the exhaust passage, andainanually operable push rod for opening the relief valveto exhaust pressure flu d acting-against one end of the feed valve,

'the feeding cylinder, a feed valve controlling V the passages exposed at both ends to pressure CERTIFICATE OF CORRECTION.

Patent No 1,743,090. Granted January 14, 1930, to

. LEWIS G. BAYLES.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 4, line 37, claim 6, insert the word "feed" before "valve"; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 4th day of February, A. D. 1930.

M. J. Moore, (Seal) Acting' Commissioner of Patents. 

